Please help me compare cab efficiency

In another thread, I was asking about increasing my volume, and after listing the specs of everything, it turns out my cabs were highly inefficient, and the cause of the lack of volume. A brief recap, I'm basically running my head through a power amp courtesy of the line out. The power amp is sending approx 450 watts to each cab. Yes, they are Behringers. Here's the cab specs:

I was told that I should look into Avatar cabs since they're basically in my price range and better quality than the Behringers. So, I did some research, went to the Avatar website, and couldn't find any tech specs for the cabs, but just the tech specs for the speakers through Eminence.

Would you guys help me in comparing the two to see how much of a difference it would make volume wise (since I already know Behringher's history, I know that the Avatar cabs would make a better value), and how they would affect my tone.

Just an FYI, I play in a metal band, and I play with a sound that's a mix between clean and distorted. (Think Meshuggah). If you want to know what it sounds like, you can hear my band through the links in my sig.

If I do replace the cabs, I would like to retain some clean low end, since I play 5'ers and 6'ers...one of which is dropped a whole step to A. (I know that the human ear doesn't really pick up the fundamental, but I still would like to get it to sound reasonably good, without farting or rattling the cab apart. Although I don't get a lot of volume, I do at least get a good sound out of the behringer setup.)

For a specific player whowants to optimise their rig, not only does it help to have a TRUTHFUL graph, but also mention of the circumstances with which it was made (half-space? anechoic? 1w/1m? 10th power? etc). But that's really only the first step if it's even part of the process. Because different basses and players and heads make for different frequency distributions and one speaker that might be loud with your style and EQ apporach may not work as well for someone who boosts or cuts altogether different freq's or uses their hands differently, or has a way-dfifferent bass (pickups, woiod choices), etc.

Since honest graphs and docs aren't available from the cab manufacturers my approach is to take a look at what the woofer specs are, and the graph from that, and it tells me a lot. Then I model it/them in a cba of about the same internal dimensions I can expect from the manufacter and that tells me something of the possibilities that porting can give to the low end.

Got to understand some stuff to do this, and as always the final step is playing/listening - in an environment you know and understand, and in a mix with other players if possible.

If the sensitivity is a single number, it is useless. It has to be a graph of sensitivity versus frequency. Given that very few makers offer such a graph, you are stuck figuring it out by ear.

My $0.02, you must be awfully loud with that rig. You have done your part, now ask the band to turn down, dagnabbit.

Click to expand...

Not as loud as you think. I should have tons of headroom, but my band only has one guitarist and a drummer. (my singer really doesn't compete volume wise).

My guitarist used to use a Crate 120watt head running through a Crate cab (essentially a half stack). He just upgraded to a Line 6 with 30W more power. He never turned up past half way on his master volume on either, but yet when I was running my power amp, (the numbers on which go up to 35), I end up turning up to like 30-32, wherever the clipping starts. This is just to compete with the drums.

As far as the graph's go, I do have to give it to Eminence for having the graphs on their page. I just wasn't sure how the dB's pan out when you have multiple speakers in a cab.

Another plus about the Eminence speakers though, is that their speakers are tested "post baffle"...approx 1meter away from the speaker being baffled for their SPL, whereas I wouldn't be surprised if Behringer basically tested right at the cone.

For a specific player whowants to optimise their rig, not only does it help to have a TRUTHFUL graph, but also mention of the circumstances with which it was made (half-space? anechoic? 1w/1m? 10th power? etc). But that's really only the first step if it's even part of the process. Because different basses and players and heads make for different frequency distributions and one speaker that might be loud with your style and EQ apporach may not work as well for someone who boosts or cuts altogether different freq's or uses their hands differently, or has a way-dfifferent bass (pickups, woiod choices), etc.

Since honest graphs and docs aren't available from the cab manufacturers my approach is to take a look at what the woofer specs are, and the graph from that, and it tells me a lot. Then I model it/them in a cba of about the same internal dimensions I can expect from the manufacter and that tells me something of the possibilities that porting can give to the low end.

Got to understand some stuff to do this, and as always the final step is playing/listening - in an environment you know and understand, and in a mix with other players if possible.

Click to expand...

I totally agree with you on this. I did as much research as I possibly could, since I have no access to Avatar cabs, I can't play through them, let alone through them in a band practice situation.

Not as loud as you think. I should have tons of headroom, but my band only has one guitarist and a drummer. (my singer really doesn't compete volume wise).

My guitarist used to use a Crate 120watt head running through a Crate cab (essentially a half stack). He just upgraded to a Line 6 with 30W more power. He never turned up past half way on his master volume on either, but yet when I was running my power amp, (the numbers on which go up to 35), I end up turning up to like 30-32, wherever the clipping starts. This is just to compete with the drums.

As far as the graph's go, I do have to give it to Eminence for having the graphs on their page. I just wasn't sure how the dB's pan out when you have multiple speakers in a cab.

Another plus about the Eminence speakers though, is that their speakers are tested "post baffle"...approx 1meter away from the speaker being baffled for their SPL, whereas I wouldn't be surprised if Behringer basically tested right at the cone.

Hmm...so I'd do better just by adding more cones then? I could have a ridiculous stack, simply by adding a 4ohm 410 cab, and daisy chaining the other two. So, essentially, if I have this correct, the daisy chained cabs will have an ohmage of 4, and a 4 ohm 410 cab will reduce the overall ohmage to 2?

I have an Avatar B115H Neo &#8211; the sensitivity is 99 dB.
You can&#8217;t always compare the sensitivity specs between different brands because they could have measured them differently.
The 99 dB seems accurate to me compared to other speakers I have.
The B115H has an internal cabinet volume of almost 5 cubic feet &#8211; the bass response is very deep for a 1x15 cab.
As far as how the dB's work when you have multiple speakers in a cab, I believe that theoretically when you go from one speaker to two identical speakers, you gain 3 dB of output &#8211; and when you go from two speakers to four identical speakers, you gain another 3 dB of output - maybe someone else can confirm that.
I am not sure about the human ear not picking up the fundamental, I think I hear it but it is not as easy to hear as the higher frequencies &#8211; maybe it is more felt than heard. When you play through a really big cab (2x15), I know you can normally hear the fundamental at least down to 50 Hz, maybe even 40 Hz.
Here are some simple things you might want to try to get some more volume out of your Behringers: put both cabs on the floor, put cabs directly on the floor without casters, make sure cabs are close together butted up against each other, set up cabs as close to the back wall and corner as you can get, run low frequency EQ (30,50,80,100Hz) at zero boost or even turned down a little, and try to set up a little further away from the guitarist and drummer.
-Les S

Thanks for the sensitivity rating on the Av. That's an additional 2dB's. I'll take that any day. But that only handles 300W power, right?

As far as band setup, my guitarist and I face the drummer, with our cabinets a few feet behind us. (sometimes I go in front of my drummer to see if it sounds much louder on his end-it doesn't), so we're kind of a triangle, with me and my guitarist angled slightly inward toward my drummer. The floors are carpeted concrete (finished basement) and surprisingly there's hardly any bounce back off the back wall of our sound (either that or we're too close to notice any difference).

Now in relation to distances from eachother, my drummer's about as near to the back of the room with still having some walkspace behind him, whilst I and my guitarist are equidistant from him. Now, between the guitarist and I, room size restricts us from moving further apart.

As far as setting up the cabs go, there's really not a lot of room to move out sideways in the practice space. That's why I have them stacked.